Seat back spring



Aug. 25, 1953 M. STUBNITZ SEAT BACK SPRING 3 Sheets-Sheet 1 Filed Nov. 16, 1949 0 0 mm m6 M W M M Aug. 25, 1953 M. STUBNITZ 2,649,395

, SEAT BACK SPRING Filed Nov. 16, 1949 3 Sheets-Sheet 2 INVENTOIL' jg. 4 I v MOM/"fee, stub/n9 BY @W] W, l A g Aug. 25, 1953 M. STUBNITZ SEAT BACK SPRING :5 Shets-Sheet 3 Filed Nov. 16, 1949 INVENTOR, Maurice Stub/n23 Y fi -044, finaw 71 7 Patented Aug. 25, 1953 SEAT BACK SPRING Maurice Stubnitz, Adrian, Mich., assignor to Stubnitz-Greene Spring Corporation, Adrian, Mich., ,a corporation of Michigan Application November 16, 1949, Serial No. 127,574

3 Claims.

This invention relates to seat back spring cushions and it is the object of the invention to provide a seat back spring more economical than the usual full depth coil spring seats, but which can compete in price with the zig-zag or wavy wire seat springs and afford greater riding comfort.

A further object of the invention is toprovide a seat back spring in which a part of the spring structure is afforded by short length coil springs and the rest of the seat back structure is afforded by spring beams which support the short length'coiled springs in spaced but yieldable relation to the seat back itself. This is done by using, at the top of the spring seat, safety pin or jack springs which space the wire mat to which the rear ends of the, coil springs are secured from the seat back.

Another feature of the invention is that the jack or safety pin spring ends are secured. in a J strip into which they are pinched and secured. The ends of the uprights which form the back of thecushion are secured in another J frame which also acts as an anchor for the trim material which may be pulled over the upper J strip and secured by hog rings in openings in the strip. The seat back cushion may be secured to the seat back frame by tabs that hang the seat back spring on the top of the seat frame. A further feature of the improved seat back spring is that the spring beams in connection with the jack springs have different amplitudes and periods of vibration than the coil springs so that the action of one set of springs dampens out the vibration of the other set so as to give a more comfortable riding where the road action is rough.

Referring to the drawings:

Fig. 1 is a small front elevation of the seat back cushion.

Fig. 2 is an enlarged cross section of the seat back cushion taken on the line 2-2 of Fig. 1.

Fig. 3 is a detail of the fastening of the coil spring to the spring beam and cross wire.

Fig. 4 is a fragmentary plan view of the improved seat back spring.

Fig. 5 is a detail of the top of the seat back cushion and a part of the seat back frame showing how one can be fastened to the other.

Fig. 6 is a fragmentary view of the lower left hand corner of the seat back frame showing how the spring is fastened in place by means of tabs.

Fig. '7 is an enlarged vertical cross section of 1 an alternative form of the invention. 7

Fig. 8 is a fragmentary plan view of the front face of the seat back cushion.

'The seat back frame is provided by the car manufacturer and consists of a box section frame member at the top made up of the channel I and the strip 2 that are spot welded together. The strip 2 extends at the top beyond the flange 3 of the channel I and forms a flange 4 over which the seat back spring is to be hooked in a way hereinafter to be described. At the bottom of the seat back frame are a pair of 2 bars 5 and 6 which are spot welded together to form a box section frame member. The 2 bar 5 is provided with struck out tabs 1 to be turned over the cross wire 8 as shown at 9 in Fig. 6. The upper box-like frame member 1-2 is secured to the lower box-like frame member 5-6 by sheet metal side members- 10. These members H! are spot welded to the top bar and the bottom bar of the frame. This completes the seat back frame structure which is furnished by the car manufacturer.

The spring manufacturer furnishes the seat back spring which is designed to be secured in place on this particular seat back frame. The back'of the seat has'a plurality of spring beams H which are united by floating cross wires [2 to the coiled springs 13 of relatively short or cutofi length. These are called floating because their two ends are entirely free and the wires are free to move forwardly and rearwardly. It will be noted that the springs of the upper two rows are approximately half the normal length of spring. They are connected together at their center ends by a border frame of wire 32. At the top of the seat back spring is provided a narrow J bar rectangular frame which consists of the upper J bar 14 which is looped over at the ends and welded to the lower J bar IS. The open channels of the two J bars face each other. The lower J bar channel [5 opens upwardly and the upper J bar channel 14 opens downwardly. This J bar frame is connected with the lower cross wire 8 by means of the strong stay wires [6 of heavy gauge. They are turned over at the upper ends and pinched in the upper J frame at [1. They are turned over at the lower ends and clipped by clip l8 to the lower cross wire 8. Only three or four of these wires need be used to bridge from the lower cross wire 8 to the upper J frame. This makes a cheap skeletonized base structure for the seat back spring.

The spring beams II which support the coil springs 13 have their ends formed into jack or safety pin springs I9. The rearward leg 20 of this safety pin spring has a bent over end 2| which is engaged in the bill of the lower J frame and staked in place. The metal tabs 22 are spot welded to the lower J frame and they have the turned over wings 23 which are shown open in Fig. 5 and which may be turned down to engage over the top edge of flange 4 of the top seat frame, therefore locating the seat back spring on the seat frame. This forms a simple and eifective way'to hang theseat' back on the seat frame.

The upholstering 24 is covered by trim mateial 25 which is secured to the top J frame through openings 26. The upper edge of the trim material may be drawn over the uphol' stery 24 and then over the J frame and the material secured to the J frame by-hogrings (not shown) that clamp through the perforationsZG in the upper J frame. lhe trim material 25aat the bottom is drawn over the lower edge'of the seat back frame and secured to the frame-itself by hog rings (not shown) that can be clamped through perforations28 in -fiange 2 1 of the lower boxsection frame.

The spring beams l i andfioating'cross wires-12- which are knotted into the lower whirls of the coiled supporting springs [3 form a-hingedlat-- ticed mat which hinges at the bottom on the clipped connections of the upright stay wires with the lower cross wire 8,. while the jack springs at the top of the spring'seat back freely,

give way and yieldingly oppose this hinging action. However the periods of vibration and the amplitudeof vibration of the coiledsprings on l. A seat back spring having a combination up-' right spring beams terminating at least one end in safety pin springs, and having floating cross members crossing the spring beams and forming therewith a latticed mat, short coil springs locked into the latticed mat at the intersections of the beams and cross members and held projecting from said mat, a border frame surrounding said coiled'springsat the'outer-ends of the springs, a base frame'to which the safety pin springs are anchored, the said base frame comprising several upright stiff wires connected together at one end by a cross wire and connected together at the other end by means of a rectangular'frame-to one bar of which is connected the legsrof the: safety pin springs and to the opposite barof which is connected the stiff upright wires.

2. The combination claimed in claim 1 in which-several of the stiff upright wire members have turned-over legs at the top of said seat spring and-in which the rectangular frame member located at the topis' made of upper and lower bars of J section in which the lower frame bar is engaged with the ends of the safety pin spring and the upper J-bar is pinched over the turnedover ends of the upright stiff wire members.

3. The combination claimed in claim 2' in which tabs that are-welded to the lower J bar member receive the lower cross wire of the seat back cush-ion and the tabs are turned over to anchor the cushion at the bottom.

MAURICE STUBNI TZ.

References Cited" in the file of this patent UNITED STATES PATENTS Number Name Date 742,251 Staples l Oct. 27, 1903- 748,433 Staples Dec. 29, 1903 813 ,92 3 Staples Feb. 27, 1906 1,915,890 Steele'et al. l June 27, 1933 2,217,290 Nordmaik Oct. 3, 1940 2,265,251 7 Reed- Dec. 9, 1941 2-,570A'09 Van Hove oct. 9,1951 

